BOSTON – PTSD and TBI are frequently co-morbid in veterans from Iraq and Afghanistan – so frequently that physicians are surprised when they find one without the other. And yet the two injuries are still mostly thought of as isolated conditions and are treated separately, even though symptoms of the two injuries are so interwoven they sometimes cannot be differentiated.

VA researchers at the Boston VA Rehabilitation Center of Excellence are looking to change that. The Translational Research Center for TBI and Stress Disorders (TRACTS) takes newly-returned servicemembers suffering from mild TBI and runs them through hours of assessment and testing in hope of better understanding the pathophysiology of TBI and how it relates to PTSD.

What they are finding is that mTBI in isolation is very rare, and that both TBI and PTSD can result in changes in brain structure, as well as a number of physical health ailments.

Through outreach by VA physicians and positive word of mouth from other veterans, veterans with mTBI are making their way to Boston to undergo the kind of comprehensive examination they feel has been lacking in previous treatment.

“We begin with the veteran rather than the diagnosis,” explained William Milberg, PhD, a research neuropsychologist and co-principal investigator of TRACTS. “We treat the veteran as a whole person whose body, brain, and mind are affected by the experiences of going into combat. We know that they have physical changes, changes to their central nervous system, and changes to their emotions.”

To identify and quantify those changes, veterans are put through more than 12 hours of testing and assessment. These include neuropsychological tests, psychiatric evaluations, a physical exam, blood work, and more than an hour and a half of advanced MRI scanning.

“Our participants end the day feeling this is the first place where people are truly interested in their experiences,” Milberg said. “Many who have been reluctant to turn to VA for help leave our study feeling very positive about VA and ready to come back for further healthcare.”

In addition to this baseline assessment, the researchers also immediately offer participants the opportunity to be part of various clinical trials, treatment for PTSD, and treatment and attention for other health problems.

“Even if they’re not in one of these therapies, we try to be there for them,” Milberg said. “We try to give them help to find community resources in any way we can.”

Since 2010, TRACTS has enrolled 227 veterans for the baseline assessment. Of those, 75 have returned one year later for a reassessment. In that time, researchers have discovered that treating PTSD and TBI separately is a lost cause. PTSD has been found to occur in 11% to 18% of returning veterans. In the TRACT study group, which is made up of patients diagnosed with mTBI, that rate is over 75%.

“In our sample, we’ve found that mTBI in isolation is extremely rare,” Milberg said. “Virtually everyone who reports mTBI has PTSD and other conditions.”

Those other conditions include early signs of vascular disease, prediabetes, high blood pressure, and a high amount of obesity. Preliminary data from brain scans of patients suggests changes in brain structure or patients with PTSD, even without considering the effects of mTBI.

These cumulative effects to brain structure mean that patients with both mTBI and PTSD are at risk to experience more severe symptoms of both conditions, and those symptoms make recovery much more difficult.

“Looking at preliminary data led us to one hypothesis going into the study that because mTBI and PTSD both impact attention, concentration, and processing speed, that [symptoms could combine] to become larger than the individual [conditions],” said Regina McGlinchey, PhD, director of TRACTS. “The combined group with mTBI and PTSD are doing exponentially worse than either group alone. From our standpoint, that puts them at a particular disadvantage in terms of engaging and benefiting from therapies.”

And it is rare that servicemembers returning with mTBI developed the condition from one single incident. Multiple blast exposures are creating sub-concussive events that accumulate over time.

“But what the sum of those events is, no one knows,” McGlinchey said. “Many of our earlier participants served in Iraq between 2004 and 2006, when [the number of blast exposures was highest]. They were in Iraq at the worst possible time.”

One of the next goals for the TRACTS researchers is a better understanding of what happens to the brain during these cumulative sub-concussive events. To that end, they are developing an animal model to assess the physics of these blast forces. “This way, we can assess what happens to the brain in a controlled way and have ways of looking at histology,” Milberg said. “Hopefully we’ll have some basis as to predict what’s happening to these servicemembers.”